Advancements in assisted phytoremediation of arsenic contaminated soils with an emphasis on biochar

Abstract

Arsenic (As) contamination of soil is a developing concern in numerous countries worldwide, as it is discharged into the soil environment through both geological and anthropogenic processes. The presence of high concentrations of As in soil may result in a decrease in the yield and safety of food commodities, as well as a reduction in nutritional quality. Consequently, it is essential to establish sustainable, cost-effective, and publicly acceptable methods for the remediation of soils that have been contaminated with As. Phytoremediation is a low-cost and environmentally sustainable technology that is used to remediate As-contaminated soils and sediments. However, its application may be impeded by the time required for remediation, climatic constraints, and low-nutrition-induced harm to plants. While assisted phytoremediation using various agents (e.g., microbes, nanoparticles, inorganic and organic materials) has shown efficient progress to remediate As-contaminated soils, biochar-enabled As phytoremediation has seen less attention until now. For phytoremediation, biochar improves soil physical and chemical qualities, which help plants grow. Biochar may enhance phytoextraction of As anions from soil. In this review, we briefly discussed sources of As, As speciation, and (phyto)remediation methods in soil; elaborated phytoremediation and various assisted phytoremediation approaches for As, and how biochar is helpful in phytoremediation of As-contaminated soil by immobilizing As in soil or via phytoextracting As from soil.